Stir yeast into warm water in a large mixing bowl; let sit for 10 minutes. Stir in molasses, caraway seeds, oil and salt. Mix well. Stir in flours, 1 cup at a time. Mix well and turn out onto a floured surface. Knead until smooth, about 8 to 10 minutes. Put dough in an oiled mixing bowl and turn to coat surface. Cover and let rise until doubled in bulk, about 1 hour.

Punch down dough and shape into 3 round loaves. Place on a buttered baking sheet, cover and let rise for 20 minutes. Preheat the oven to 400 degrees and place a shallow pan with 1" of hot water on the rack below where the bread will be baking. Beat egg lightly with milk and brush on the loaves. Bake for 15 minutes, then brush with the egg mixture once again. Bake another 15 minutes or until loaves are golden brown and sound hollow when tapped. Cool on wire racks. Makes 3 loaves.